last day: Grebe, Sauer (etwas Seyfried)

Question 1

Hormones, produced in the pituitary gland

Answer 1

Antidiuretic Hormone (ADH) = Vasopressin
Increases the water permeability of the kidney collecting ducts (Sammelkanäle) --> Increased water resorption

Oxytocin
Stimulates milk secretion and uterus contraction

Question 2

pituitary gland front lobe consist of

Answer 2

pitulary front lobe (with capillaries and endocrine cells) and
neutral pituitary

Question 3

thyroid gland is filled with

Answer 3

thyroid gland follicle - colloid (enriched hormone structures)

Question 4

thyroid gland produce

Answer 4

thyreoglobulin (only known ionidized biomolecule)

bind: TBG; Thyroxin-binding globulin

Question 5

contraction of heart muscle - which structural components (proteins) do you need?

Answer 5

actin, binding tropomyosin, binding troponin (SU:
TnT = Tropomyosin-binding subunit
TnC = Ca2+-binding subunit
TnI = inhibitory subunit)
binding triggered by Ca2+

Question 6

action potential (+20-+30 mV)
How do we get there?

Answer 6

• K-permeability decreases with time & Na-permeability („funny current“) increases –> instabile resting potential
–> slow depolarisation (= pace maker potential)
• at threshold potential: voltage-gated Ca-channels open: Depolarisation
• Excitation transmission onto other cardiomyocytes via gap junctions

Question 7

Excitation transmission heart

Answer 7

contractive wave starts in sinus knot (ca2+ triggered) –> atrioventricular knot (his bundle) –> tawara branches via purkinje fibers to chamber myocardium

Question 8

resistance

Answer 8

Flow ungefähr 1/R
in blood vessels: L (length) and eta (viscosity of liquid) are constant, just r (vasoconstriction = Gefäßverengung) variabel
ateriols with varible radius

Question 9

colloid osmotic pressure

Answer 9

osmotic pressure due to disolved proteins

Question 10

Pressure is

Answer 10

highest in aorta and lowes in hohlvene

Question 11

ER

Answer 11

1. Discovered in 1945 in cells of chicken embryos
2. Present in all eukaryotic cells
3. It is an intracellular compartment: A lipid bilayer membrane enclosing an inner space (lumen)
4. It is a network of interconnected membrane tubules and cisternae (“reticulum”) stretching across the entire cytoplasm (“endoplasmic”)
5. It is the location where membrane proteins,
   soluble cargo proteins and lipids are synthesized
6. From the ER, membrane proteins, soluble cargo
   proteins and lipids are transported to other
   compartments or to the extracellular space along
   the secretory pathway

Question 12

Protein quality controle by ER

Answer 12

unfolded –> URP (unfolded protein response) is released –> misfolded ERAD ER associated degedation pathway –> retrotranslocation (protein to cytosol and cleaved by 26S proteasome)

Question 13

Golgi apparatus

Answer 13

• the Golgi was discovered by Italian physician Camillo Golgi (1897)
• it is the organelle where cell wall components, such as pectins and hemicellulose, are synthesized [cellulose instead is synthesized at the plasma membrane]
• it is the location where protein glycosylation continues (it starts in the ER)

Question 14

The trans-Golgi network (TGN)

Answer 14

It is a tubular-vesicular organelle with a pleiomorphic shape (it has an undifined, irregular shape)
The trans-Golgi network (TGN) derives from the Golgi through the maturation of the cistearnae

Question 15

Clathrin mediated endocytosis adaptors

Answer 15

LOLITA, T PLATE, AP-2 Complex, AtEH1, AtEH2, TM, TWd40-1, TWd40-2

Question 16

Clathrin mediated endocytosis recruitment factors

Answer 16

TASH3, CAP1, AtECA4

Question 17

Endocytosis

Answer 17

a cellular process in which substances are brought into the cell. The material to be internalized is surrounded by an area of cell membrane, which then buds off inside the cell to form a vesicle containing the ingested material. Endocytosis includes pinocytosis (cell drinking) and phagocytosis (cell eating). It is a form of active transport.

Question 18

Secretion

Answer 18

is the movement of material from one point to another, e.g. secreted chemical substance from a cell or gland. In contrast, excretion, is the removal of certain substances or waste products from a cell or organism. The classical mechanism of cell secretion is via secretory portals at the cell plasma membrane called porosomes.[1] Porosomes are permanent cup-shaped lipoprotein structure at the cell plasma membrane, where secretory vesicles transiently dock and fuse to release intra-vesicular contents from the cell.

Question 19

Animals: Lysosomes

Answer 19

small
• unrelated to cell size
• hydrolytic
• low pH
• main function is degradation

Question 20

Vacuoles in plants

Answer 20

very large: 30 – 90% of cellular volume
• energy efficient way to increase cell size
• not always with hydrolytic activity
• not always low pH
• functionally diverse

Question 21

How to degrade transmembrane proteins?

Answer 21

The Multivesicular Body/Prevacuolar Compartment

Question 22

Bulding head groups of PIPs can be recognized by

Answer 22

lipid binding domains (LBDs)

Question 23

Steps of Autophagy

Answer 23

Induction (Stress) –> Phagophore formation (first steps may occur at ER) –> Autophagosome with double membrane –> outer membrane – tonoplast fusion –> degradation

Question 24

SCF Complexes and Protein Degradation

Answer 24

Ubiquitin: activation by E1
Ubiquitin is transfered to E2
Ubiqutinated E2 forms complex with E3 ligase and target
target ubiquitinated by E2/E3
target protein is degardated by 25S proteosom
SCF: Skp1/Cullin/F-Box
Nomenclature: SCFTIR1 : F-Box Protein is TIR1 Transport Inhibitor Resistant1

Question 25

Repressor Retargeting as another Example of Signal Transduction by Inactivation of Repressors

Answer 25

COP1 represses the HY5 TF and many light-regulated genes involved in red light (phytochrome) and blue light (cryptochrome) signaling.
Modification of the subcellular localization of the COP1 repressor as a means of regulating its action.

Question 26

What Is Cell Polarity?

Answer 26

A persistent asymmetrical, distribution of structures (or molecules) along an axis

Question 27

Why Do Plant Cells Need to Become Polar?

Answer 27

orientation towards or away from an energy source (e.g. Light)
sensing of external stimuli (e.g. light and gravity)
surface extension for nutrient uptake (e.g. root hairs)
surface extension and protection against herbivores (trichomes)
polar transport of molecules
directional signalling during plant development
cell fate segregation during plant development

Question 28

GNOM Is Required for Coordinate

Answer 28

Polar Positioning of the Auxin Efflux Carrier PIN-FORMED1 (PIN1) in the Embryo (GNOM goes with arf1)

Question 29

The Vesicle Trafficking Inhibitor

Answer 29

Brefeldin A (BFA) Reversibly Inhibits PIN1 Protein Recycling from/to the Basal Membrane

Question 30

fluorescence excitment

Answer 30

Green fluorescence 488 nm
Red fluorescence 561 nm
locally excite with UV (365 or 405 nm) to photo-convert from green to red fluorescence
track resulting photo-converted red fluorescence at 561 nm excitation
newly synthesized green protein at 488 nm excitation